Metamath Proof Explorer


Theorem fin1a2lem10

Description: Lemma for fin1a2 . A nonempty finite union of members of a chain is a member of the chain. (Contributed by Stefan O'Rear, 8-Nov-2014)

Ref Expression
Assertion fin1a2lem10 A A Fin [⊂] Or A A A

Proof

Step Hyp Ref Expression
1 eqneqall a = a [⊂] Or a a a
2 tru
3 2 a1i a =
4 1 3 2thd a = a [⊂] Or a a a
5 neeq1 a = b a b
6 soeq2 a = b [⊂] Or a [⊂] Or b
7 unieq a = b a = b
8 id a = b a = b
9 7 8 eleq12d a = b a a b b
10 6 9 imbi12d a = b [⊂] Or a a a [⊂] Or b b b
11 5 10 imbi12d a = b a [⊂] Or a a a b [⊂] Or b b b
12 neeq1 a = b c a b c
13 soeq2 a = b c [⊂] Or a [⊂] Or b c
14 unieq a = b c a = b c
15 id a = b c a = b c
16 14 15 eleq12d a = b c a a b c b c
17 13 16 imbi12d a = b c [⊂] Or a a a [⊂] Or b c b c b c
18 12 17 imbi12d a = b c a [⊂] Or a a a b c [⊂] Or b c b c b c
19 neeq1 a = A a A
20 soeq2 a = A [⊂] Or a [⊂] Or A
21 unieq a = A a = A
22 id a = A a = A
23 21 22 eleq12d a = A a a A A
24 20 23 imbi12d a = A [⊂] Or a a a [⊂] Or A A A
25 19 24 imbi12d a = A a [⊂] Or a a a A [⊂] Or A A A
26 unisnv c = c
27 vsnid c c
28 26 27 eqeltri c c
29 uneq1 b = b c = c
30 uncom c = c
31 un0 c = c
32 30 31 eqtri c = c
33 29 32 eqtrdi b = b c = c
34 33 unieqd b = b c = c
35 34 33 eleq12d b = b c b c c c
36 28 35 mpbiri b = b c b c
37 36 a1d b = b [⊂] Or b b b b c b c
38 37 adantl b Fin [⊂] Or b c b c b = b [⊂] Or b b b b c b c
39 simpr b Fin [⊂] Or b c b c b b
40 ssun1 b b c
41 simpl2 b Fin [⊂] Or b c b c b [⊂] Or b c
42 soss b b c [⊂] Or b c [⊂] Or b
43 40 41 42 mpsyl b Fin [⊂] Or b c b c b [⊂] Or b
44 uniun b c = b c
45 26 uneq2i b c = b c
46 44 45 eqtri b c = b c
47 simprr b Fin [⊂] Or b c b c b b b b b
48 simpl2 b Fin [⊂] Or b c b c b b b [⊂] Or b c
49 elun1 b b b b c
50 49 ad2antll b Fin [⊂] Or b c b c b b b b b c
51 ssun2 c b c
52 51 27 sselii c b c
53 52 a1i b Fin [⊂] Or b c b c b b b c b c
54 sorpssi [⊂] Or b c b b c c b c b c c b
55 48 50 53 54 syl12anc b Fin [⊂] Or b c b c b b b b c c b
56 ssequn1 b c b c = c
57 52 a1i b b c b c
58 eleq1 b c = c b c b c c b c
59 57 58 imbitrrid b c = c b b b c b c
60 56 59 sylbi b c b b b c b c
61 60 impcom b b b c b c b c
62 uncom b c = c b
63 ssequn1 c b c b = b
64 eleq1 c b = b c b b c b b c
65 49 64 imbitrrid c b = b b b c b b c
66 63 65 sylbi c b b b c b b c
67 66 impcom b b c b c b b c
68 62 67 eqeltrid b b c b b c b c
69 61 68 jaodan b b b c c b b c b c
70 47 55 69 syl2anc b Fin [⊂] Or b c b c b b b b c b c
71 46 70 eqeltrid b Fin [⊂] Or b c b c b b b b c b c
72 71 expr b Fin [⊂] Or b c b c b b b b c b c
73 43 72 embantd b Fin [⊂] Or b c b c b [⊂] Or b b b b c b c
74 39 73 embantd b Fin [⊂] Or b c b c b b [⊂] Or b b b b c b c
75 38 74 pm2.61dane b Fin [⊂] Or b c b c b [⊂] Or b b b b c b c
76 75 3exp b Fin [⊂] Or b c b c b [⊂] Or b b b b c b c
77 76 com24 b Fin b [⊂] Or b b b b c [⊂] Or b c b c b c
78 4 11 18 25 2 77 findcard2 A Fin A [⊂] Or A A A
79 78 3imp21 A A Fin [⊂] Or A A A